The Last Black
by chasin' fantasy
Summary: She would be a double agent, the best duelist of her generation, and the most cunning soldier at Hogwarts. She was also a scared, untrusting child who would one day inherit a powerful seat in the Wizengamot. The members of the Noble and Most Ancient House of Black do not show weakness, so Cassiopeia always hides hers.
1. Prologue

**Prologue**

Halloween night of 1981 will always be a day that lives in infamy amongst Great Britain's wizarding population. The defeat of You-Know-Who by Harry Potter as a baby is what comes to mind for most wizards. A dangerous man was vanquished after he made a child an orphan. For the Tonks family, 31 October 1981 is significant for a slightly different reason. Like the Dursleys, the Tonks would raise a parentless relative after a dangerous man caused the lost her parents.

Andromeda Tonks was relaxing on the sofa with a Butterbeer to decompress from convincing the hyper, "I'm not sleepy Mum," seven-year-old Nymphadora to go to sleep when there was frantic knocking on the door. Few people could pass the heavy barriers that guarded the house from Death Eaters, who would be more than happy to kill the blood traitor and mudblood, and even less would be at the door this late at night.

"I'll get it." Ted Tonks told his wife as he passed her on the way to the door. He pulled out his wand, and held it at the ready.

Ted looked out the peephole, and lowered his defenses a minuscule amount as he unlocked the door. As soon as he opened the door, a tall man with long black hair and the refined beauty of an aristocrat barged into the house carrying a smiling infant. Ted quickly recovered being practically trampled by his wife's cousin, and his wife leapt off the sofa.

"Sirius!" Andromeda practically yelled, but stopped herself quickly so she didn't wake her daughter sleeping upstairs. "What are you doing here?"

"I need you to watch her for me Dromeda." Sirius said as he placed the child in his cousin's arms. The baby immediately took interest in the hair of her new holder, and proceeded to start yanking it.

"Why-?" Ted started to ask while his wife was occupied with stopping the baby from wrenching all the hair off her scalp.

"I don't have time for any questions. I need to leave now, and you're the only one I trust to care for her." Sirius said frantically.

"Sirius what is happening?" Andromeda questioned in a calm voice in hopes to sooth her cousin.

"I can't explain, but I promise I'll be back for her tomorrow morning." Sirius said as he backed away.

He ran out of his cousin's house into the chilly October night without another word. Husband and wife exchanged confused looks over the baby, who was trying to poke out Andromeda's eye. They could only hope that when Sirius returned for his daughter he would explain his bizarre actions.

Sirius Black never came back to the Tonks House after that night. The next morning the wizarding world would be celebrating the defeat of you-Know-Who, but the Tonks were concerned about the new parentless leader of the Noble and Most Ancient House of Black. The infant gained more power that night than the Tonks knew how to handle.

Sirius lost everything when he left to chase his traitor friend. He never saw his cousin or her husband again, nor did his daughter ever smiled at him again. The young woman he met after his escape never forgave him for abandoning her for petty revenge, and she did not let her father attempt to fix their broken relationship. While Sirius Black spent twelve years rotting away in Azkaban, Cassiopeia Black was raised by her second cousins to one day lead the wizarding population into greatness.


	2. End of Normalcy

There are turning points in poetry, a volta they're called, where the poem shifts, causing the reader to reassess the message of the poem. Turning points like these also exist in people's lives. It's when a child becomes an adult, or one piece of information is uncovered causing a person's view on the world to flip upside down. The shifts can be subtle or sudden. They can hit a person like a pleasant summer breeze or like a 7.0 magnitude earthquake.

The death of Cedric Diggory was a subtle turning point in Cassiopeia Black's life. It marked the beginning to the end of carefree days spent in the Slytherin common room laughing at Draco Malfoy's antics. Soon, there would be no more weekends spent under the tutelage of her regent to the Noble and Most Ancient House of Black, Lord Lucius Malfoy. She would no longer spend lazy summer days lounging around the Tonks' house reading books or playing wizarding chess with Cousin Ted. There would be no more societal affairs where she gossiped in the corner with friends, and no more trips to the Greengrass vacation home in France with Daphne and Tracy.

Cedric Diggory's untimely demise marked the end of Cassiopeia's childhood, and started a war that she along with Hogwarts's student body were not ready to fight. She had no idea how much affect Cedric's death would have on her life until she stepped off of the Hogwarts Express several weeks later.

Cassiopeia Black stepped off the Hogwarts Express with Daphne Greengrass, Tracy Davis, Theodore Nott, and Blaise Zabini. They all gave each other their final goodbye hugs and promises to write over the summer. Cass began to look around the platform for Andromeda and Ted Tonks so that she could go back home and start her summer of relaxation. She did not spend much time in search for them before a tall dark-skinned man came up to her.

"Cassiopeia Black?" He asked her.

"Yes."

"I'm Auror Kingsley Shacklebolt," he told her. "I was sent to collect you. You're spending the summer at a different residence this year."

"Since when was this decided?"

"Since Dumbledore informed me to pick you up from the train station and take you to your summer home."

Shacklebolt then proceed to pick up Cass's trunk and walk towards the exit with it. As she followed him, Cass spotted Lord and Lady Malfoy looking around everywhere for their son.

"Excuse me for a minute Auror Shacklebolt," Cass said as she walked towards the Malfoys."

"Lord Malfoy," Cass said to her wizarding regent. "I believe you might need to go on the train to collect Draco."

"Why is that Miss Black?"

"Because the last time I saw him was a few hours ago, and he said that he needed to go talk to Potter. There is a good chance he, Gregory, and Vincent are lying unconscious somewhere on the train."

With those words Cass walked off into the muggle world with Kingsley Shacklebolt, and into life altering summer.

Cassiopeia Black was not expecting to walk half an hour across muggle London. She figured that they would take a Portkey, apparate, or even take a muggle car. When Auror Shacklebolt suddenly stopped in front of a muggle neighborhood, Cass was grateful to the end of the walk, yet confused at the sudden stop in the middle of muggle London. She was not wearing the proper shoes for her trek across London, and her faith in the auror was waning as she looked around their surroundings spotting nothing magical.

"Here." Auror Shacklebolt said as he handed Cass a piece of parchment. "Read quickly and memorize."

Cass looked down at it, and her confusion increased when she read:

 _The Headquarters of the Order of the Phoenix may be found at number twelve, Grimmauld Place, London._

"What is this?" She asked her auror escort.

"We'll discuss it inside." Auror Shacklebolt said walking towards the new house that appeared between number eleven and thirteen.

Number 12 Grimmauld Place used to be a beautiful London home. For generations, society events were hosted here, and every witch and wizard coveted an invitation. However, during the reign of Walburga Black everything about the house changed. Not even the most influential wizard could enter the house if they were not of the purest blood. Gone were the parties that had been held since the Enlightenment, and the esteem of the house had all but vanished.

When Cass stepped through the threshold of the house, she encounters a dark, dusty, creepy hallway. It seemed more like a villain's lair in the muggle films she watched with Cousin Ted than any sort of headquarters named after a bird of fire. Then, she heard two set of footsteps. One was light and hurried, and the other was heavier and seemed almost hesitant.

As her vision adjusted to the darkness surrounding her, Cass spotted the two approaching figures. One was a witch with bright pink hair who Cass had grown up idolizing, and she had a smile plastered on her face that Cass recognized all too well. It was a smile that told Cass that her idol had done something the Cass would not like, and was trying to ease the blow. The other was a man with long black hair, and Cass recognized him from the wanted posters that covered Hogsmeade and Diagon Ally two years ago.

"I thought you were dead." Cass told her biological father.

"Cass," her cousin said in a warning voice that sounded eerily like woman who raised them both.

"No, Nymphy." Cass sharply told her cousin before turning back to the man who abandoned her. "I thought that you were dead. I thought that you had drowned in the sea during your escape from Azkaban, and later I thought you had died from the Dementor's Kiss."

"Let me explain Cass," her father said.

"Cassiopeia."

"What?"

"Only friends and family can call me Cass, and after you apparently survived and did not reach out to me you are no longer family."

"I had to lie low and not be found." He tried to explain.

At that moment, the front door opened again, and the entire Weasley clan entered the house. Their shouting and laughter filled the house, but oblivious to the tension in the room or its dark ambiance did not lessen.

"Hi Sirius," the youngest Weasley boy said. "It's been a long time since I last saw you. I'm glad that you're no longer living off rats in that cave."

When Cass heard this, she rolled her eyes and scoffed.

"Of course," she muttered under her breath.

"What's a Slytherin doing here?" asked the same freckled boy.

"Apparently, I'm spending the summer with you." Cass said seething with anger. "Also, I have a name Weasley, and I'm sure if you search through that dense head of yours you'll remember it in about a month."

With that, Cass turned towards the stairs and started to stomp up them.

"Where do you think you're going?!" Sirius yelled after her.

"To Uncle Regulus's room!" She yelled back. "If I'm correct this is your childhood home, so I'll just be in the room of my Slytherin Black predecessor."

The last thing she heard before she went in search of her dead uncle's room was her father's confused voice asking, "how did she figure this out, and how does she know about Regulus?"

At the top of the first flight of stairs, Cass nearly trampled over an old house elf. She was about to apologize, but when he started spouting off about blood traitors and how his mistress wouldn't approve, Cass promptly changed her mind. She drew upon all the lessons in ways to gain respect through fear her regent taught her to put the house elf in his place.

"Quiet," Cass said in a low steady voice.

The house elf immediately stopped cursing Cass, and looked at her with a bewildered expression. Cass supposed that no one had ordered the house elf around recently, and that he had managed to get away with such a disrespectful attitude.

"Show me the way to Regulus Black's bedroom." Cass ordered the house elf in a tone that conveyed she would not tolerate any insolence.

All the house elf did was continue to grumble under his breath has he walked further up the stairs. Cass followed him, and soon they came to a locked door with a sign hanging on it.

"Do not enter without the express permission of Regulus Arcturus Black," Cass read out loud much to her displeasure.

The house elf just smirked up at Cass enjoying her dilemma of not being able to enter. Cass just looked at the wrinkled old creature and told him to unlock the door. Regulus would not care if any one entered his room because he was very much dead. At least he was according to the lessons Lord Malfoy and Cousin Andromeda gave her on the Black family history.

The house elf finally found a key and opened the door grumbling and cursing the entire time. The room was decked out in Slytherin emerald and silver along with a thick layer of dust and grime.

"When was the last time you cleaned this room?" Cass asked the house elf. Upon having no answer, she looked down and he was gone.

 _"_ _Just brilliant,"_ Cass thought as she jumped on the bed disturbing the thin layer of dust covering it. _"I get to spend my summer in a house filled with thick-headed Gryffindors and a house elf that despises me. At least it can't get any worse."_

Cassiopeia Black should have known better than to jinx her summer with one simple thought. Ten minutes later Mrs. Weasley burst into her room, and forced Cass downstairs to help make dinner. Cass had never had to help with any sort of back-from-school dinner. Since Nymphadora came back from school that first Christmas when Cass was five, the Tonks family went to a muggle fish and chips stand nearby. They would eat greasy food and drink the sugary, muggle soft drinks. The four of them would wander around discussing school and just catching up.

Walking into the kitchen, Cass had immediately entered a war zone. The twins were throwing vegetables at the younger two Weasleys who were throwing flour and raw meat in retaliation. Cass turned on her heel faster than a snitch and exited into the dining room. She saw Nymphadora sitting at the table reading the _Daily_ _Prophet_.

"How long do I have to stay here?" she asked her cousin.

"All summer." Nymphadora replied without looking up from the paper.

"So, I'm not going to spend any time at home?"

"This is technically your home."

"It's my ancestral house that is my birthright, and I own it since I'm the last Black whose still alive and not a felon from Orion Black's direct descendants."

"Exactly. It's your home."

"It's not my home. It's my property, and besides it has none of my books, pictures, or random items scattered around my actual home that I've collected over the years."

"What can I say to you to convince you this is your home?" Tonks said as she laid down the newspaper and looked at her cousin.

"Nothing, because it's not my home." Cass shrugged.

"You're staying here this summer whether you like it or not because Dumbledore said so."

Cass scoffed at that response.

"Dumbledore is my headmaster. That means he can tell me what to do at school but not outside it. Look around Nymphadora. This is not Hogwarts."

"DON'T CALL ME NYMPHADORA!" Her cousin yelled.

"DON'T TELL ME HOW TO SPEND MY SUMMER!" Cass screamed as she slammed her fist into the table.

The two cousins were glaring at each other when Molly Weasley walked into the dining room.

"Shouldn't you be helping out in the kitchen young lady?" Mrs. Weasley asked Cass.

"I will once the food fight is over." Cass replied without breaking eye contact with Tonks.

With those words, Cass stomped out of the dining room without sparing a glance towards her cousin. She ran up the stairs and slammed the door of her temporary room shut. Cass knew she was in for a summer of hell, and it had not even been a full day away from Hogwarts.


End file.
